Q: Ever seen this? My young dogwood leaves were very delayed and deformed. Strange gnarled masses forming. No blooms. Our lawn service sprayed it in mid-March with horticultural oil for scale. Also treated the surrounding lawn in May with broadleaf weed control.
A: This looks like a perfect example of herbicide injury.
The twisting of the leaves is a classic symptom of weed killer action. If a weed control chemical is applied on a windy day or if it is put onto the root zone of some trees, leaf injury results.
It is possible the dogwood will grow out of this injury. You’ll just have to wait and see.
Ask your maintenance company to show you the label for their weed control product. Most labels instruct the user not to apply onto the root zone of trees.